Stripper packer unit



March 3 1, 1970 B. WILLIAMS 1 $503,617

STRIPPER PACKER UNIT Filed Aug. 28, 1967 2 Sheets-Sheet 1 I INVENTOR. 22 BOB WILLIAMS ;4I I BY met/mm FIG. 4

ATTOR NEY March 31, 1970 B. WIYLLIAMS 3,503,617

STRIPPER PACKER UNIT Filed Aug. 28, 1967 2 Sheets-Sheet 2 Fl(; 3 INVENTOR.

BOB WILLIAMS ATTORNEY United States Patent O 3,503,617 STRIPPER PACKER UNIT Bob Williams, 823 Cavanaugh Road, Fort Smith, Ark. 72901 Filed Aug. 28, 1967, Ser. No. 663,839 Int. Cl. F16j 15/32, 15/56 U.S. Cl. 277-9 Claims ABSTRACT OF THE DISCLOSURE A Stripper packer unit for rotary drilling rigs, and the like, wherein a iubber packing or stripper element is bonded to a support ring member. The support ring may be quickly and easily threaded onto a drilling head assembly or the like, thus facilitating the installation and/ or replacement of the stripper packer unit on the drilling head.

This invention relates to improvements in well drilling apparatus and more particularly, but not by way of limitation, to a stripper packer unit for rotary drilling rigs, and the like.

In rotary drilling of oil and gas well bores, or the like, the drill bit is normally carried at the lower end of the drill pipe or drill string. The drill pipe is rotated by means of a kelly located at the surface of the ground, and as the drilling operation progresses, the drill string moves downwardly within the bore. Of course, when a sufficient length of drilling has occurred, it is necessary to add additional sections of pipe to the drill string to continue the drilling operation. Well casing is usually installed or set in the upper portion of the well bore and extends downwardly therein whereby the drill string extends therethrough during the drilling operation. A drilling head assembly, or the like, is usually secured to the upper end of the well casing to provide a seal around the rotating and vertically moving drill pipe. It is common practice to provide a packing unit known as a stripper rubber or stripper packer, at the lower end of the drilling head assembly. The stripper member is stationary and comprises a rubber or resilient member adapted for engagement with the outer periphery of the drill string. Of course, a considerable amount of friction may result from the rotation of the drill string, which wears away the rubber material. In addition, the vertical movement of the drill string in the well bore adds to the wear on the rubber, and the vertical upward movement of the drill string frequently tends to cause the rubber stripper to try to pull through itself or substantially turn inside out.

The present invention contemplates a novel stripper packer unit for rotary drilling apparatus which is particularly designed and constructed to overcome the disadvantages of presently available devices of this type. A main hinge or support body is provided for the packer unit, and is internally threaded for ease of installation on the lower end of a drilling head assembly, or the like. The rubber stripper element is efliciently bonded or molded to the support body in a manner substantially precluding any accidental separation of the rubber from the body. In addition, the body is provided with a stiffener member and cooperating stop ring for substantially eliminating any tendency of the rubber element to turn back within itself as the drill pipe is pulled upwardly therethrough.

It is an important object of this invention to provide a novel stripper packer unit for a rotary drilling apparatus particularly designed and constructed for facilitating installation thereof on a drilling head assembly, or the like.

Another object of this invention is to provide a novel stripper packer unit for a rotary drilling apparatus wherein the rubber stripper element is bonded to the support body in a manner substantially precluding accidental loss of the rubber during utilization of the unit.

A further object of this invention is to provide a novel stripper packer unit for a rotary drilling apparatus wherein the tendency for the rubber element to pull through itself is substantially eliminated.

A still further object of this invention is to provide a novel stripper packer unit which is simple and efficient in construction and economical and durable in operation.

Other and further objects and advantageous features of the present invention will hereinafter more fully appear in connection with a detailed description of the drawings in which:

FIGURE 1 is an elevational view, partly in section, of a stripper packer unit embodying the invention.

FIGURE 2 is a plan view of a support body for a stripper packer unit embodying the invention.

FIGURE 3 is a sectional view taken on line 3-3 of FIGURE 2.

FIGURE 4 is a sectional view taken on line 44 of FIGURE 2.

FIGURE 5 is a sectional view taken on line 55 of FIGURE 2.

Referring to the drawings in detail, reference character 10 generally indicates a stripper packer unit comprising a support body 12 having a yieldable or resilient stripper element 14 bonded thereto as will be hereinafter set forth. The support body 12 comprises a substantially cylindrical central sleeve member 16 having an inner diameter of a suflicient size for receiving the lower end of a drill head assembly (not shown) such as that disclosed in my co-pending application filed Sept. 16, 1966, and entitled Drilling Head Assembly, issued on Sept. 10, 1968, as Patent No. 3,400,938. Of course, it is to be noted that there is no intention to limit the use of the unit 10 with a drilling head assembly of any type, and the unit 10 is for utilization in any suitable manner and with any suitable equipment, as is well known. The inner periphery of the sleeve 16 is threaded at 18 for threaded engagement with a drilling head assembly, or the like, for securing the unit 10 thereto.

An inwardly directed annular flange 26 is provided on the inner periphery of the sleeve 16 to provide a stop ring for limiting the threaded engagement between the body 12 and the drilling head assembly, or other device to which the unit 10 is secured. The sleeve 16 extends axially or longitudinally beyond the stop ring 20 to provide a stiffening member 22 and the stiffening element or member 22 is provided with a plurality of circumferentially spaced elongated slots or apertures 24 for a purpose as will be hereinafter set forth.

An outwardly extending circumferential flange 26 is provide around the outer periphery of the sleeve 16 and is spaced slightly from the upper end thereof as viewed in the drawings. The flange 26 may be integral with or suitably secured to the sleeve 16 and the outer periphery thereof is provided with an upwardly extending cylindrical flange 28. A plurality of circumferentially spaced apertures 30 are provided in the flange 26, but it is to be noted that the cylindrical flange 28 is substantially continuous around the outer periphery of the flange 26. A plurality of spaced radially outwardly extending boss members 32 are interposed in the flange 26, as particularly shown in FIGURE 2, and each boss 32 is provided with a threaded bore 34 extending longitudinally therethrough. A set screw, or the like (not shown) may be threadedly inserted through the bores 34 for engagement with the outer periphery of the drilling head assembly, or the like, for facilitating securing of the unit 10 thereto.

The stripper member 14 is preferably constructed from rubber, or other suitable flexible or resilient material, and comprises a substantially cylindrical sleeve portion 36 bonded to the support body 12 in a manner as will be hereinafter set forth. The lower end of the stripper element 14, as viewed in the drawings, is substantially conical or inwardly tapered and terminates in a reduced neck portion 38 having an inner periphery '40 of a diameter or size complementary to the outer diameter of the drill pipe (not shown) with which the unit is to be utilized whereby the inner periphery of the reduced neck 38 provides a sealing engagement around the drill pipe. It is also preferable to provide an outwardly tapered or beveled portion 42 at the lower end of the inner bore 40, and the lower end of the outer periphery of the neck 38 may also be beveled as shown at 44, if desired.

In addition, the inner periphery 40 may be either a smooth or straight cylindrical configuration, or may be provided with a slightly tapered portion as shown at 46 in FIGURE 1, if desired. The compound or dual type configuration for the inner periphery 40 provides an efiicient sealing engagement with the drill pipe, and particularly facilitating the wiping action against the outer periphery of the drill pipe when the pipe is moving either downwardly or upwardly within the well bore (not shown).

The stripper element 14 is molded or otherwise bonded to the body 12 in any well known manner (not shown), and the rubber material, or other yieldable material from which the element 14 is molded flows into and through the apertures 24 of the cage-like lower extension 22 as well as the apertures 30- of the flange 26. Thus, the material of the element 14 completely surrounds the cage 22 and the flange 26. The stop ring 20 and cage 22 cooperate to substantially preclude any tendency of the element 14 to pull through itself when the drill pipe is pulled upwardly through the well bore.

The stripper packer unit 10 may be quickly and easily threaded onto the lower end of the drilling head assembly, or the like (not shown), and set screws may be inserted through the bores 34 for engagement with the outer periphery of the drilling head assembly for facilitating the securing of the unit 10 thereon. The inner periphery 40 of the neck 38 of the element 14 will bear against the outer periphery of the drill string or drill pipe (not shown) which extends through the drilling head assembly during the drilling operation. The element 14 provides an eflicient seal and wiping action against the outer periphery of the drill pipe as the pipe is rotated and moves vertically downward with respect thereto. When it is necessary to pull the drill pipe from the well bore for any reason, the stripper element 14 will wipe the outer periphery thereof clean, and the stiffener or cage 22 and stop ring 20 will resist any upward movement of the element 14 during the upward movement of the drill pipe with respect thereto.

When the stripper element 14 becomes worn or damaged for any reason, the entire unit 10 may be quickly removed from the drilling head assembly by backing off the set screws and unthreading the body 12 from the engagement with the drill head assembly and the entire unit 10 may be replaced. The rubber material may be removed from the body by the application of sufficient heat, or by any well known manner, and a new element 14 may be molded or bonded onto the ring 12. Thus, the unit 10 may be relatively easily and economically repaired or reconstructed for reuse.

From the foregoing it will be apparent that the present invention provides a novel stripper packer unit for rotary drilling installations Which may be quickly and easily installed around the outer periphery of the drill string. The stripper element is bonded to the support ring in a manner substantially precluding loss of the stripper element, and substantially eliminating any inward turning or tendency of the stripper element to pull through itself. The stripper packer unit may be readily removed and replaced in the event of damage or wear, and may be easily reconstructed for reuse. The novel stripper packer unit is simple and efficient in operation and economical and durable. in construction.

Changes'may be made in the combination and arrangement of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims, without departing from the spirit of the invention.

What is claimed is:

1. A stripper packer unit comprising a support body adapted for disposition around a drill string, yieldable stripper element means molded to the support body and having a portion thereof in engagement with the outer periphery of the drill string, means provided on said support body for reinforcing the stripper element, and means provided on said support body for facilitating the molding of the stripper element thereto, said reinforcing means including an inwardly directed stop ring, and a substantially cylindrical sleeve member extending from said stop ring and disposed within the yieldable stripper element.

2. A stripper packer unit comprising a support body adapted for disposition around a drill string, yieldable stripper element means molded to the support body and having a portion thereof in engagement with the outer periphery of the drill string, means provided on said sup port body for reinforcing the stripper element, and means provided on said support body for facilitating the molding of the stripper element thereto including an outwardly extending circumferential flange provided around the outer periphery of the support body and embedded within the stripper element, said flange and reinforcing means being provided with a plurality of spaced apparatus whereby the stripper element completely surrounds the flange and reinforcing means for substantially precluding accidental separation of said stripper element and support body.

3. A stripper packer unit comprising a support body adapted for disposition around a drill string, yieldable stripper element means molded to the support body and having a portion thereof in engagement with the outer periphery of the drill string, means provided on said support body for reinforcing the stripper element, and means provided on said support body for facilitating the molding 0f the stripper element thereto, said reinforcing means comprising an inwardly directed stop ring and a substantially cylindrical sleeve member extending from said stop ring, said cylindrical sleeve member being embedded within the yieldable stripper element, and said means for facilitating molding of the stripper element to the support body comprising a plurality of spaced apertures provided in the cylindrical sleeve member whereby the yieldable stripper member completely encompasses the sleeve, and an outwardly extending circumferential flange provided around the outer periphery of the support body and embedded with the stripper element, said flange being provided with a plurality of spaced apertures whereby the stripper element completely surrounds the flange for facilitating the molding of the stripper element to the support body.

4. A stripper packer unit comprising a support body adapted for disposition around a drill string, said support body being provided with a central bore for receiving the drill string therethrough, said bore being provided with a threaded portion for facilitating securing of the support body around the drill string, a yieldable stripper element bonded to the support body, an inwardly directed circumferential ring provided in the bore, a substantial cylindrical stiffener sleeve extending axially from said stop ring and embedded within the stripper element, said stiffener sleeve being provided with a plurality of apertures for facilitating the molding of the stripper element to and around the stiffener sleeve, an outwardly extending circumferential flange provided around the outer periphery of the support body and embedded within the stripper element, said outwardly extending circumferential flange being provided with a plurality of circumferentially spaced apertures for facilitating the molding of the stripper element to the support body.

5. A stripper packer unit as set forth in claim 4 wherein a plurality of radially extending apertured bosses are provided on the outwardly extending circumferential flange for facilitating retaining of the support body in position around the drill string.

References Cited UNITED STATES PATENTS 10 SAMUEL ROTHBERG, Primary Examiner US. Cl. X.R. 

